1. Field of the Invention
This invention relates to a Static Random Access Memory (SRAM), and more particularly to an improved means for reading out data stored in memory cells.
2. Description of the Prior Art
In the prior art SRAM, as shown in FIG. 1, data is written into a memory cell (11) through a common switching transistor (17) controlled by address signals (A) (A). The memory cell (11) includes a Flip-Flop circuit (14) which consists of inverter circuits (18) (19) in which an output signal of the inverter circuit (19) is fed back to the input of inverter circuit (18) at the input node (A).
In the memory, when the data stored in the memory cell (11) is read out of the memory cell (11), the data is changed because stray capacitance C.sub.1 existing on a data line (13) is considerably larger than capacitance C.sub.2 of memory cell (11). Namely, in case that the stored data is "0", node A is at a low level and bus line (13) is at a high level, electric charge on the data line (13) moves to node A, which causes the stored data to change. On the other hand, in case that stored data is "1", node A is at a high level and the bus line (13) is at a low level, electric charge on node A moves to the data line (13). The above described misbehavior is a fatal drawback in the prior art memory system.